Table 2.

Summary of D50 and k values and EQD2 values with 95% confidence interval for developing high-grade subjective xerostomia as scored by subjective scoring systems

	Subjective xerostomia LENTSOMA	Subjective xerostomia RTOG
Combined superficial lobes
CLPS
D50 (Gy; 95% confidence interval)	34.6 (30.6–38.8)	36.1 (27.0–45.1)
EQD2 D50 (Gy; 95% confidence interval)	35.8 (31.6–40.1)	37.3 (27.9–46.6)
k	4.6 (1.5–7.6)	2.9 (–0.2–6.2)
BSLPS
D50 (Gy; 95% confidence interval)	32.6 (24.3–41.1)	39.0 (29.5–48.5)
EQD2 D50 (Gy; 95% confidence interval)	33.7 (25.1–42.5)	40.3 (30.5–50.1)
k	3.3 (0.4–7.6)	3.2 (0.9–5.5)

CLPS, contralateral parotid sparing; BSLPS, bilateral superficial lobe parotid sparing.

LENTSOMA, Late Effects of Normal Tissue- subjective, objective, management analytical.

RTOG, Radiation Therapy Oncology Group.